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Friday, April 1, 2011

Alzheimer's-Like Brain Changes Found in Cognitively Normal Elders With Amyloid Plaques

ScienceDaily

Friday, April 1, 2011

ScienceDaily (Apr. 1, 2011) — Researchers using two brain-imaging technologies have found that apparently normal older individuals with brain deposits of amyloid beta -- the primary constituent of the plaques found in the brains of Alzheimer's disease patients -- also had changes in brain structure similar to those seen in Alzheimer's patients. Results of the study, which has received early online publication in the Annals of Neurology, may help identify individuals who could be candidates for therapies to prevent the development of dementia.

"Our findings support the theory that Alzheimer's disease begins many years before symptoms appear and that amyloid plaque is an early sign of this process," says Keith Johnson, MD, Massachusetts General Hospital (MGH) Imaging, senior author of the study. "We see that when amyloid deposits are present, even in cognitively normal individuals, the degenerative changes of Alzheimer's are underway. Long-term studies to track these changes and observe how they evolve are ongoing."

Definitive diagnosis of Alzheimer's disease requires finding amyloid plaques and neurofibrillary tangles in the brain at autopsy. In recent years it has been possible to detect amyloid in living brains by PET scanning with an imaging agent known as Pittsburgh Compound B (PiB). Plaques have been observed in the brains of apparently healthy individuals, as well as those with dementia, but whether the presence of plaques indicates the early stages of Alzheimer's disease is not yet known.

High-resolution magnetic resonance imaging studies have identified characteristic changes in brain structure -- thinning of key cortical regions and reduced volume of structures such as the hippocampus -- in persons with mild cognitive impairment, in individuals known to carry gene mutations that directly cause Alzheimer's disease and in diagnosed Alzheimer's patients. A recent study reported similar brain changes in some cognitively normal elders but did not distinguish those who had amyloid deposits from those who did not.

The current study involved 87 cognitively normal older individuals and 32 patients diagnosed with mild Alzheimer's -- matched for age, gender and education -- who had enrolled in the long-term Harvard Aging Brain Study. Participants underwent both high-resolution MR imaging of brain structure and PET scanning with PiB to detect amyloid plaques. The results showed that those cognitively normal individuals who had amyloid plaques also had structural changes similar to but less pronounced than the neurodegenerative changes seen in the symptomatic patients. Structural changes were most evident in areas comprising what is called the default network, which is known to be affected early in the course of Alzheimer's disease.

"If amyloidosis -- deposits of amyloid plaques -- in the brains of clinically normal people is associated with Alzheimer's-like neurodegeneration, then amyloidosis itself may signify 'preclinical' AD," say Johnson, an associate professor of Radiology at Harvard Medical School. "We need to learn more about how long it takes a normal person with amyloid to develop AD, whether there are critical 'second hit' factors that convert amyloidosis to Alzheimer's disease, and if there are measures that can halt the process of neurodegeneration."

Alex Becker, PhD, of MGH Imaging, is lead author of the Annals of Neurology report. Additional co-authors are Jeremy Carmasin, Jacqueline Maye, Bruce Fischl, MD, and Douglas Greve, PhD, MGH Imaging; Trey Hedden, PhD and Deepti Putcha, Martinos Center for Biomedical Imaging at MGH; Dorene Rentz, PsyD, Gad Marshall, MD, and Reisa Sperling, MGH and Brigham and Women's Neurology; Randy Buckner, PhD, MGH Psychiatry; Stephen Salloway, MD, Brown University; and Donald Marks, MD, Tufts University School of Medicine. The study was supported by grants from the National Institutes of Health, Massachusetts Alzheimer's Disease Research Center, Howard Hughes Medical Institute, the Alzheimer's Association and the Charles Farnsworth Trust.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

J. Alex Becker, Trey Hedden, Jeremy Carmasin, Jacqueline Maye, Dorene M. Rentz, Deepti Putcha, Bruce Fischl, Douglas N. Greve, Gad A. Marshall, Stephen Salloway, Donald Marks, Randy L. Buckner, Reisa A. Sperling, Keith A. Johnson. Amyloid-β associated cortical thinning in clinically normal elderly. Annals of Neurology, 2011; DOI: 10.1002/ana.22333

Exercise Is Key for People With Arthritis: Expert

HealthDay News

Friday, April 1, 2011

FRIDAY, April 1 (HealthDay News) -- Exercise is a good way for people with arthritis to control pain and improve physical function, says an expert.

"People who have arthritis are often scared to exercise because they think they will hurt themselves, but the condition will only get worse if people don't get moving," Valerie Walkowiak, medical integration coordinator at the Loyola Center for Fitness in Maywood, Ill., said in a news release.

"The best way to start is to talk to your doctor about exercising and then work with a therapist or personal trainer to establish guidelines. Be proactive, and take it one step at a time," she advised.

Exercise offers a number of benefits for people with arthritis, including: increasing muscle strength and endurance to improve joint stability; preserving and restoring joint motion and flexibility; and boosting aerobic conditioning to improve mental health and decrease the risk of other diseases.

About 50 million adults in the United States have arthritis, according to the U.S. Centers for Disease Control and Prevention.

Osteoarthritis is the most prevalent form. It occurs when cartilage deteriorates, leaving nearby joints with no cushion between bones. Many people also suffer from rheumatoid arthritis, which occurs when inflammation in the joint causes it to lose shape and alignment.

The best type of exercise program can depend which form of arthritis a person has, but some workouts benefit all patients.

All arthritis sufferers can benefit from stretching to increase range of motion around an affected joint, Walkowiak said. "The type of stretching one should do depends on which joint is affected."

Arthritis sufferers may also want to try light weights a few times a week to build muscle strength and low-impact aerobic exercise such as walking.

"Start slow, with 10 to 15 minutes of aerobic exercise every other day, to see how it impacts your body," Walkowiak said. "As your body adapts to the new routine, gradually increase duration to 30 to 45 minutes."

Other good exercises can include water aerobics, stationary cycling, gardening, swimming, yoga and Tai-Chi.

More information

The Arthritis Foundation has more about exercise and arthritis.

Brain Research Reveals Possible Causes of Sudden Infant Death Syndrome

ScienceDaily

Friday, April 1, 2011

ScienceDaily (Apr. 1, 2011) — New research published today in The Journal of Physiology sheds light on areas of the brain thought to be the root cause of Sudden Infant Death Syndrome (SIDS) -- the poorly understood condition also known as 'cot death'.

The research looks at specific areas of the brain and how they communicate to control breathing. It builds on previous studies that suspected abnormalities in the brain may be responsible for SIDS. It is hoped this research may vastly improve understanding of the condition.

The team from Macquarie University in Sydney have identified two areas of the brain that work together to control breathing and swallowing to enable breathing without choking -- they hope that by understanding how these areas should work, they can identify what may be going wrong in SIDS babies.

Professor Paul Pilowsky, lead author of the paper, commented: "Until now, the centres in the brain that coordinate breathing and swallowing were poorly understood, but our research has finally teased apart the two mechanisms in the brain, demonstrating how they work together in the presence of an irritant.

"If irritants such as food or water 'go down the wrong way' and enter the airway, a powerful protective response is initiated in the brain to stop breathing and prevent foreign matter entering the lungs. Abnormalities in this reflex may underlie a number of life threatening conditions, including SIDS."

This protective reflex brings the vocal chords together and initiates coughing and swallowing. It is vital to everyone, but babies in particular as they have a tendency to regurgitate liquids after feeding and saliva tends to pool in their throats. It is also risky -- without breathing, blood oxygen levels can drop to dangerously low levels, heart rate slows and blood is re-routed to the brain, depriving and potentially damaging other organs.

"The closing of the airway in adults is only a small compromise as breathing is only stopped temporarily. But for babies the response has more radical implications, particularly if breathing stops for a long time, as they can't take in oxygen or get rid of carbon dioxide.

"The timing of breathing and swallowing is exquisitely coordinated. We suspect that coordination of the two may be going awry in SIDS, but to be sure of this, we need to know how the brain organises this response in the first place," added Prof. Pilowsky.

To understand how the central nervous system controls breathing and swallowing, the team recreated the brain and body's response to a throat irritant using electrical stimulation of the nerve (the superior laryngeal nerve) which normally carries information from the larynx (or voicebox) to the brain, to initiate the reflex response.

By artificially generating a response and measuring the neurotransmitters that indicate how the different regions of the brain are talking to one another, the team hopes to have a better understanding of what is going on in the brain to disrupt the reflex and cause breathing to stop for long periods.

"The next step is to work out why these regions 'decide' whether breathing should be stopped. The eventual hope is to have the ability to manipulate these two systems separately to prevent the excessively long breathing arrest that may cause SIDS," concluded Professor Pilowsky.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

Q.-J. Sun, T. G. Bautista, R. G. Berkowitz, W.-J. Zhao, P. M. Pilowsky. The temporal relationship between non-respiratory burst activity of expiratory laryngeal motoneurons and phrenic apnoea during stimulation of the superior laryngeal nerve in rat. The Journal of Physiology, 2011; DOI: 10.1113/jphysiol.2010.203794

Toxins in baby food might affect hormones: study

By Adam Marcus

Reuters Health

Friday, April 1, 2011

NEW YORK (Reuters Health) – Infant formula and solid baby food frequently contain fungus-derived hormones that have been shown to cause infertility in mammals, Italian researchers report.

Scientists at the University of Pisa report that as many as 28 percent of samples of milk-based baby formulas they tested were contaminated with the fungal hormones, known as mycoestrogens.

They tested 185 formula samples and 44 samples of meat-based baby food from a total of 21 brands commonly sold in Italy.

The substances detected in the baby products included zearalenone and its derivatives, which comes from Fusarium, a large family of fungi common in farm settings.

Although zearalenone and related chemicals that resemble the hormone estrogen have been linked to infertility in mammals, especially pigs, it's not clear whether babies exposed to the compounds through food or formula would be at risk for any reproductive problems later in life.

Previous research has shown that the body rapidly breaks down zearalenone into byproducts that pose no health threat.

Still, the Italian researchers say their findings merit follow-up and ought to prompt closer scrutiny of baby formula and baby foods for the presence of these and other toxins.

"Our study shows the presence of mycoestrogens in infant food," Francesco Massart, who led the study, told Reuters Health. "This is likely to have greater implications for infants and young children than for adults having a more varied diet."

Mycoestrogens such as zearalenone are a fact of life for commercial agriculture. They are present in crops like corn, wheat and soy that are used for both human consumption and animal feed. Cattle yards in the United States regularly use one such substance, alpha-zeralanol, as a growth stimulant for the animals, although the European Union banned this practice in the mid-1980s.

The Italian group sought to determine whether zearalenone and similar chemicals might be making their way into infant foods. The answer proved to be yes.

Massart and his colleagues analyzed 185 samples from 14 brands of infant formula containing cow's milk. They also tested 44 samples of baby foods, from seven brands, containing beef, chicken, turkey, calf, horse, rabbit, ham and lamb.

Zearalenone appeared in 17 (9 percent) of the formula samples, and two derivatives of the molecule, alpha- and beta-zeralenol, were present in about a quarter of the samples. Among the meat-based baby foods, only the alpha- and beta-zeralenol derivatives were present in a less than a quarter of the samples.

Concentrations of mycoestrogens varied widely but in general, the levels detected were well below the World Health Organization's provisional maximum tolerable daily intake of 0.5 micrograms per kilogram of body weight. Average concentrations of beta-zeralenol in infant formula were four times the recommended maximum, however.

Although Massart acknowledged that many questions remain about the possible link between mycoestrogens and harm to humans, he said the findings should give pause to parents who use baby formula.

"Children, and in particular preterm newborns, are potentially exposed to higher dose of mycotoxins during their early phases of life, but no one knows the long-term effects," he said.

Animal research and the few available human studies suggest the early mycotoxin exposures may affect human health, Massart noted. "Specific studies should be initiated that allow the establishment of safe levels of zearalenone metabolites in feed materials and compounded feeds, particularly for infants and children of different ages, as they are considered to be the most sensitive to environmental chemicals."

Gilbert Ross, a physician and medical director of the American Council on Science and Health, a New York-based advocacy group, disagreed. "Detecting something in food does not mean it's harmful," Ross said.

"Further, the detection methods found (the contaminants) but at levels far too low to affect human health, including that of babies. As the authors themselves point out, the presence of these substances in food products are of 'little significance' because the body rapidly breaks them down and excretes them," Ross said

Source: http://bit.ly/ekM2N8

The Journal of Pediatrics, online March 11, 2011.

Laughter Not Only Feels Good, It's Good for the Heart

HealthDay News

Friday, April 1, 2011

FRIDAY, April 1 (HealthDay News) -- Having a good laugh on April Fool's Day or any other day of the year helps relieve stress and benefits your blood vessels, an expert says.

"Laughter increases blood flow and improves the function of blood vessels. Reducing stress is especially beneficial for persons who have hypertension [high blood pressure]," Dr. Vivienne Halpern said in a Society for Vascular Surgery news release.

April is National Stress Awareness Month in the United States.

"Laughter reduces the level of stress hormones [cortisol, epinephrine, dopamine and growth hormone] and increases the level of health-enhancing hormones [endorphins and neurotransmitters]," Halpern explained. "This can result in a stronger immune system and fewer physical effects of stress."

Along with reducing stress and improving blood flow and blood vessel function, laughter helps relax muscles and creates a sense of well-being, she added.

High blood pressure is linked to stroke, a leading cause of death in the United States.

More information

The American Academy of Family Physicians has more about coping with stress.

Got a Craving for Fast Food? Skip the Coffee, Study Suggests

ScienceDaily

Friday, April 1, 2011

ScienceDaily (Apr. 1, 2011) — Eating a fatty fast food meal is never good for you, but washing that meal down with a coffee is even worse, according to a new University of Guelph study.

Researcher Marie-Soleil Beaudoin has discovered not only that a healthy person's blood sugar levels spike after eating a high-fat meal, but that the spike doubles after having both a fatty meal and caffeinated coffee -- jumping to levels similar to those of people at risk for diabetes.

"The results tell us that saturated fat interferes with the body's ability to clear sugars from the blood and, when combined with caffeinated coffee, the impact can be even worse," said Beaudoin, a PhD student who conducted the study with U of G professors Lindsay Robinson and Terry Graham. "Having sugar remain in our blood for long periods is unhealthy because it can take a toll on our body's organs."

Published in the Journal of Nutrition, the study is the first to examine the effects of saturated fat and caffeinated coffee on blood sugar levels using a novel fat cocktail which contains only lipids. This specially designed beverage allows researchers to accurately mimic what happens to the body when we ingest fat.

For the study, healthy men drank about one gram of the fat beverage for every kilogram of body weight for their first meal. Six hours later, they were given a second meal consisting of a sugar drink.

Typically when we ingest sugar, the body produces insulin, which takes the sugar out of the blood and distributes it to our muscles, said Beaudoin.

But the researchers found that the fatty meal affected the body's ability to clear the sugar out of the blood. The subjects' blood sugar levels were 32 per cent higher than they were when the men had not ingested the fat cocktail.

The researchers also tested the impact of caffeinated coffee combined with the fatty meal. For this test, participants received the equivalent of two cups of caffeinated coffee five hours after ingesting the fat beverage. An hour later, they were then given the sugar drink.

The results showed blood sugar levels increased by 65 per cent compared to what they were when participants had not ingested the fat and caffeinated coffee.

"This shows that the effects of a high-fat meal can last for hours," said Beaudoin. "What you eat for lunch can impact how your body responds to food later in the day."

Besides testing the participant's blood sugar levels, the researchers looked at gastro-intestinal effects by measuring incretin hormones released by the gut after ingesting the fat. These hormones signal the pancreas to release insulin to help clear the blood of sugar. The researchers discovered these hormones' responses to carbohydrates are blunted after ingesting the fat beverage.

"Ultimately we have found that fat and caffeinated coffee are impairing the communication between the gut and the pancreas, which could be playing a role in why participants couldn't clear the sugar from their blood as easily," said Beaudoin.

The results of the study are particularly important for people at risk for metabolic diseases and Type 2 diabetes, she adds.

"We have known for many years that people with or at risk of Type 2 diabetes should limit their caffeine intake. Drinking decaffeinated coffee instead of caffeinated is one way to improve one's glucose tolerance. Limiting the intake of saturated fatty acids found in red meat, processed foods and fast food meals is also beneficial. This study has shown that the affects of these foods can be severe and long lasting."

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

M.-S. Beaudoin, L. E. Robinson, T. E. Graham. An Oral Lipid Challenge and Acute Intake of Caffeinated Coffee Additively Decrease Glucose Tolerance in Healthy Men. Journal of Nutrition, 2011; 141 (4): 574 DOI: 10.3945/jn.110.132761

Thursday, March 31, 2011 

More suicidal thoughts with antidepressant: report

By Frederik Joelving

Reuters Health

Thursday, March 31, 2011

NEW YORK (Reuters Health) – A new report from the drug company GlaxoSmithKline concludes that its antidepressant Paxil might make adults with major depression more likely to become suicidal.

But the rate of suicide attempts was low, at 0.34 percent for people on Paxil and 0.05 percent for people who got sham treatment with a placebo pill in clinical trials.

And it couldn't be entirely ruled out that the difference was due to chance, according to the report, published in the Journal of Clinical Psychiatry.

"The scientific evidence does not establish that paroxetine" - the ingredient in Paxil -- "causes suicide, suicide attempts, self-harm or suicidal thinking," said Sarah Alspach, a spokeswoman for the drug company.

"Nonetheless, all patients who are started on antidepressant therapy should be monitored appropriately and observed closely for clinical worsening, suicidality, or unusual changes in behavior."

In general, antidepressants can be extremely helpful for people with depression. The American Academy of Family Physicians says on its web site, "Most people who have depression get better with treatment that includes these medicines."

But the link between suicide risk and antidepressants has long been a thorny issue for regulators and drugmakers alike. The current data were initially published in 2006 on GlaxoSmithKline's website in response to widespread concern.

In 2004, the U.S. Food and Drug Administration (FDA) issued a warning that children and adolescents taking antidepressants might have an increased risk of suicidal thoughts and behaviors.

Specifically, the agency found that 4 percent of children taking antidepressants in clinical trials thought about killing or harming themselves, or actually attempted suicide.

By comparison, only 2 percent of children on fake medications did so.

In 2006, the FDA extended its warning to include young adults up to age 25. All antidepressant labels must now carry a "black box" warning stating that they can increase a person's likelihood of suicidal thoughts and behaviors.

For adults, though, the picture has been less than clear-cut.

GlaxoSmithKline's report was based on 57 trials of Paxil for different psychiatric illnesses, involving a total of nearly 15,000 patients. Overall, the drug did not appear to increase suicidal thoughts and behavior.

The authors did see a difference when zooming in on 18- to 24-years-olds; 2.58 percent of Paxil users thought about or attempted suicide, compared to 1.29 percent of study participants on placebo treatment.

Again, that finding could have been due to chance because of the low rate of suicidal behavior.

The 19 trials that included only people with major depressive disorder also found a difference. Among 3,455 Paxil users, 0.34% attempted or succeeded at suicide, compared to 0.05% of the 1,978 people getting placebo.

And most of the suicide attempts were seen in young adults.

Despite those troubling findings, the report notes that Paxil was effective overall at treating symptoms of mental illness.

"Paxil has proven efficacy and has helped many people battling mental illness lead more productive, happier lives," GSK's Alspach told Reuters Health in an email.

According to the Centers for Disease Control and Prevention, antidepressants are one of the most commonly prescribed drug classes in the U.S. One study found that 10 percent of the U.S. population was taking these medications in 2005.

Last year, researchers found that the suicide risk among children is virtually the same for a wide range of antidepressants -- including Prozac (fluoxetine), Zoloft (sertraline) and Paxil (paroxetine).

People who are taking antidepressants should never stop taking them without talking to their doctor, because stopping too quickly can cause side effects.

People who are having suicidal thoughts should talk to their doctor; they can also call the free, 24-hour National Suicide Prevention Lifeline at 1-800-273-TALK (8255), or go online to http://www.suicidepreventionlifeline.org/

Source: http://bit.ly/hADiCH

Journal of Clinical Psychiatry, online February 22, 2011.

US Cancer Death Rates in Decline: Annual Report Focuses on Brain Tumors

ScienceDaily

Thursday, March 31, 2011

ScienceDaily (Mar. 31, 2011) — Lung cancer death rates in women have fallen for the first time in four decades, according to an annual report on the status of cancer published online March 31 in the Journal of the National Cancer Institute. The drop comes about 10 years after lung cancer deaths in men began to fall, a delay that reflects the later uptake of smoking by women in the middle of the last century.

Overall, the cancer death rate has continued a decline that began in the early 1990s according to the report, which is published each year by the National Cancer Institute (NCI), the North American Association of Central Cancer Registries (NAACCR), the Centers for Disease Control and Prevention (CDC), and the American Cancer Society.

Lead author Betsy A. Kohler of NAACCR and colleagues collected information on cancer incidence (new cases) from the NCI, CDC, and NAACCR and on cancer deaths from the CDC's National Center for Health Statistics.

Incidence rates (new cases) also fell overall, according to the report. For certain cancers, however, incidence and/or deaths increased.

Highlights from this year's report, which covers periods from 1992 through 2007, include the following:

Overall cancer incidence rates declined about 1 percent a year and overall death rates fell an average 1.6 percent a year between 2003 and 2007.

Among men, incidence of liver, kidney, and pancreatic cancer and melanoma increased from 2003-2007. Death rates increased for three of these cancers--liver and pancreatic cancer and melanoma.

Among women, incidence of kidney, thyroid, and pancreatic cancer as well as leukemia and melanoma increased from 2003-2007. Death rates increased for pancreatic and liver cancer. Death rates for uterine cancer, after falling from 1975 through 1997, increased in the following decade.

Trends in death rates during the most recent 10- and 5-year periods decreased for seven of the top 15 cancer types in both men and women (colon and rectum, brain [malignant], stomach, and kidney cancers, and non-Hodgkin lymphoma, leukemia, and myeloma); for cancers of the lung, prostate, and oral cavity in men; and for breast and bladder cancers in women. The decreases for ovary, lung, and cervical cancers were limited to the most recent 5-year period.

Among children, cancer death rates continued a decline that began in the 1970s; however, the incidence of childhood cancer increased by about 0.6 percent a year from 1992-2007.

Black men and women had the highest death rates overall but also the largest declines in death rates from 1998 through 2007. For new cancers, black men had the highest overall incidence rates. White women had the highest incidence rates among women.

Brain Tumors

This year's report has a special section on brain tumors and includes, for the first time, data on non-malignant brain tumors diagnosed from 2004 through 2007. The authors found that the incidence of neuroepithelial brain tumors, a common, usually malignant type, fell an average 0.4 percent a year from 1987 through 2007. This decrease balanced an increase of about 2 percent a year from 1980 through 1987, leaving long-term incidence unchanged.

Other highlights from the brain tumor section of the report:

Nonmalignant tumors were about twice as common as malignant tumors among adults aged 20 and older.

Brain tumors in children were much rarer than in adults but much more likely to be malignant; 65.2 percent were malignant in children vs. 33.7 percent in adults.

Tumors of the neuroepithelial tissue were the most common kind of malignant brain tumor and glioblastoma was the most common subtype of neuroepithelial tumors.

The most common nonmalignant tumor was meningioma, and it was 2.3 times more common in women than in men.

In conclusion the authors write that the "decreases in overall cancer incidence and death rates in nearly all racial and ethnic groups are highly encouraging."

However, they note that the number of people in the U.S. age 65 years and older, people that are at increased risk of many common types of cancer, is expected to double in size by 2030 compared to 2000.

"Even with declining cancer incidence rates," they write, "the absolute number of individuals diagnosed with cancer will continue to increase because of these population changes…." They conclude that "effective management of the cancer burden will require the application of sound cancer control strategies in prevention, detection, treatment, and survivorship, as well as resources to provide good quality of care."

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

Betsy A. Kohler et al. Annual Report to the Nation Shows Continuing Decline in Cancer Mortality. Journal of the National Cancer Institute, March 31, 2011 DOI: 10.1093/jnci/djr141

Tetanus Still Diagnosed in U.S., Although It's Preventable

HealthDay News

Thursday, March 31, 2011

THURSDAY, March 31 (HealthDay News) -- While a tetanus shot can shield Americans from the potentially fatal infection, sporadic cases do still occur among those who went unvaccinated, the U.S. Centers for Disease Control and Prevention reported Thursday.

Tetanus is a rare but potentially deadly disease caused by the toxin of Clostridium tetani bacteria, which is found in soil and animal excrement. Since 1947, reported cases of tetanus in the United States have fallen more than 95 percent, and tetanus deaths have decreased 99 percent, according to the study.

Nevertheless, according to data from the National Notifiable Diseases Surveillance System, there were 233 cases of tetanus (lockjaw) reported in the United States between 2001 and 2008. The death rate was 13.2 percent in the 197 cases with known outcomes, the CDC said.

The risk of death was highest among people older than 65, diabetics, and those who hadn't been vaccinated or didn't have up-to-date vaccinations, said the researchers.

"Sporadic cases in adults still occur, especially in those not vaccinated during childhood," the researchers said.

Vaccination can prevent tetanus, and health care providers should ensure that all their patients, especially those older than 65 and those with diabetes, have up-to-date vaccinations, the researchers said.

A complete vaccine series should be given to children at ages 2, 4, 6, 18 months and at 4 to 6 years. A booster dose is needed when children are 11 to 12 years old and every 10 years after that, said the study authors.

The findings appear in the April 1 issue of Morbidity and Mortality Weekly Report.

More information

The Immunization Action Coalition has more about tetanus.

Wednesday, March 30, 2011 

54 Beneficial Compounds Discovered in Pure Maple Syrup

ScienceDaily

Wednesday, March 30, 2011

ScienceDaily (Mar. 30, 2011) — University of Rhode Island researcher Navindra Seeram has discovered 34 new beneficial compounds in pure maple syrup and confirmed that 20 compounds discovered last year in preliminary research play a key role in human health.

On March 30 at the 241st American Chemical Society's National Meeting in Anaheim, Calif. the URI assistant pharmacy professor is telling scientists from around the world that his URI team has now isolated and identified 54 beneficial compounds in pure maple syrup from Quebec, five of which have never been seen in nature.

"I continue to say that nature is the best chemist, and that maple syrup is becoming a champion food when it comes to the number and variety of beneficial compounds found in it," Seeram said. "It's important to note that in our laboratory research we found that several of these compounds possess anti-oxidant and anti-inflammatory properties, which have been shown to fight cancer, diabetes and bacterial illnesses."

These discoveries of new molecules from nature can also provide chemists with leads that could prompt synthesis of medications that could be used to fight fatal diseases, Seeram said.

"We know that the compounds are anti-inflammatory agents and that inflammation has been implicated in several chronic diseases, such as heart disease, diabetes, certain types of cancers and neurodegenerative diseases, such as Alzheimer's," Seeram said.

As part of his diabetes research, Seeram has collaborated with Chong Lee, professor of nutrition and food sciences in URI's College of the Environment and Life Sciences. The scientists have found that maple syrup phenolics, the beneficial anti-oxidant compounds, inhibit two carbohydrate hydrolyzing enzymes that are relevant to Type 2 diabetes management.

The irony of finding a potential anti-diabetes compound in a sweetener is not lost on Seeram. "Not all sweeteners are created equal," he said.

Among the five new compounds is Quebecol, a compound created when a farmer boils off the water in maple sap to get maple syrup. It takes 40 liters (20.5 gallons) of sap to make 1 liter (2 pints) of syrup.

"Quebecol has a unique chemical structure or skeleton never before identified in nature," Seeram said. "I believe the process of concentrating the maple sap into maple syrup is what creates Quebecol. There is beneficial and interesting chemistry going on when the boiling process occurs. I believe the heat forms this unique compound."

Seeram said he and his team chose the common name of Quebecol for the new compound to honor the province of Quebec in Canada, which leads the worldwide production of maple syrup. Seeram's research was supported by the

Conseil pour le developpement de l'agriculture du Quebec (CDAQ) and Agriculture and Agri-Food Canada (AAFC) on behalf of the Canadian maple syrup industry.

"Producers, transformers and partners of the Canadian maple industry believe that investing in maple syrup knowledge and innovation will bring the products to another level in a few years," said Serge Beaulieu, president of the Federation of Quebec Maple Syrup Producers and member of the Canadian Maple Industry Advisory Committee.

"Quebec Maple Syrup Producers are especially proud to be leading this long-term innovative strategy on behalf of the Canadian industry and with the talented scientists of the Canadian Maple Innovation Network."

Genevieve Beland, marketing director of the Federation added, "Maple products' composition is unique and we are at the starting point of a new era. Ten years from now consumers will appreciate 100 percent pure maple products because they are delicious, natural and have a number of healthy compounds."

"As we continued our research in the past year, we were astonished when the number of beneficial compounds that we isolated is now more than double the original amount," said Seeram, who is now releasing his findings.

Seeram is the organizer of the daylong symposium on "Bioactives in Natural Sweeteners," and is joined by scientists from Canada, Japan, Mexico and the United States to discuss natural sweeteners. Seeram's collaborations with Angela Slitt, assistant professor of biomedical sciences in URI's College of Pharmacy and Professor Lee, will also be presented during the meeting.

Seeram's findings will be detailed in his article recently accepted for publication in the Journal of Functional Foods. The title of the paper is "Quebecol, a novel phenolic compound isolated from Canadian maple syrup." In addition, Seeram and Lee's work on diabetes and maple syrup will also be published in an upcoming edition of the Journal of Functional Foods.

"I can guarantee you that few, if any, other natural sweeteners have this anti-oxidant cocktail of beneficial compounds; it has some of the beneficial compounds that are found in berries, some that are found in tea and some that are found in flaxseed. People may not realize it, but while we have a wide variety of fruits and vegetables in our food chain, maple syrup is the single largest consumed food product that is entirely obtained from the sap of trees," Seeram said.

Reiterating a statement he made last year, Seeram said no one is suggesting that people consume large quantities of maple syrup, but that if they are going to use a sweetener on their pancakes, they should choose pure maple syrup and not the commercial products with high fructose corn syrup.

"Pure maple syrup is not only delicious, it is so much better for you," Seeram said.

Funding of CDAQ is provided through Agriculture and Agri-Food Canada's Advancing Canadian Agriculture and Agri-Food program. AAFC has been able to provide financial support for maple syrup research through the program 'Growing Canadian Agri-Innovations'.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Longer Breast-Feeding May Be Key to Bigger Brains

HealthDay News

Wednesday, March 30, 2011

WEDNESDAY, March 30 (HealthDay News) -- Longer periods of pregnancy and breast-feeding in mammals are associated with larger brain growth in offspring, which explains why human babies remain dependent on their mother for so long, say researchers.

They also said the findings from their study of humans and 127 other mammal species offer further proof that breast-feeding is good for brain development and support the World Health Organization's recommendation that babies should be breast-fed exclusively for their first six months of life, followed by continued breast-feeding (along with other foods) up to age 2 or longer.

The researchers at the University of Durham in the U.K. found that brain size relative to body size was most closely associated with maternal investment -- the length of time a mother spends carrying her offspring in pregnancy and how long she suckles her young.

The length of pregnancy determines offspring's brain size at birth and the amount of time spent suckling affects brain growth after birth.

For example, humans have nine-month pregnancies and breast-feed their babies for up to three years. This is necessary to fuel the growth of the brains, which have an average volume of 1,300 cubic centimeters (cc) in adults. Fallow deer have about the same body weight as humans but are only pregnant for seven months, followed by a suckling period of up to six months. Their adult brain size is 220cc, six times smaller than the human brain.

"We already know that large-brained species develop more slowly, mature later and have longer lifespans, but what has not always been clear is why brains and life histories are related," lead investigator and anthropology professor Robert Barton said in a university news release.

"One theory is that large brains increase lifespan by making the animal more generally flexible in its behavioral responses to unpredictable challenges, permitting slower life histories. However, our findings suggest that the slow-down in life histories is directly related to the costs rather than the benefits of growing a large brain. The necessary benefits to offset these costs could come in other ways, such as improving specific perceptual and cognitive abilities, rather than through some generalized flexibility," he explained.

The study was published in this week's issue of the Proceedings of the National Academy of Sciences.

More information

The U.S. National Women's Health Information Center has more about breast-feeding.

Diabetes tied to higher Parkinson's disease risk

By Amy Norton

Reuters Health

Wednesday, March 30, 2011

NEW YORK (Reuters Health) – People with diabetes may have a slightly increased risk of developing Parkinson's disease, a new study suggests -- though the reasons for the link, researchers say, are far from clear.

The study, of nearly 289,000 older U.S. adults, found that those with diabetes at the outset were more likely to be diagnosed with Parkinson's over the next 15 years.

Of 21,600 participants with diabetes, 172 (0.8 percent) were eventually diagnosed with Parkinson's. That compared with 1,393 cases (0.5 percent) among the 267,000 men and women who were diabetes-free at the study's start.

When the researchers accounted for other factors -- like age, weight and smoking habits -- diabetes itself was linked to a 41 percent increase in the risk of future Parkinson's.

That, however, does not prove that diabetes is a cause of Parkinson's, and the reasons for the connection remain unknown, said senior researcher Dr. Honglei Chen, of the U.S. National Institute of Environmental Health Sciences.

"Really, the evidence at this time is very preliminary," Chen told Reuters Health.

People with diabetes, he said, should simply continue to do the things already recommended for their overall health -- eating a well-balanced diet and getting regular exercise.

Chen and his colleagues report the findings in the April issue of the journal Diabetes Care.

Diabetes and Parkinson's disease would seem, at first, to be unrelated.

Diabetes arises when the body can no longer properly use the blood-sugar-regulating hormone insulin. Parkinson's is a brain disease in which movement-regulating cells in the brain die off or become disabled, leading to symptoms like tremors, rigidity in the joints, slowed movement and balance problems.

But Chen said the connection between diabetes and Parkinson's risk could mean that the two diseases share some underlying mechanisms.

One possibility, he speculated, is chronic, low-level inflammation throughout the body, which is suspected of contributing to a number of chronic diseases by damaging cells. Oxidation - the process fought by anti-oxidants - is another.

On the other hand, Chen and his colleagues say, there might be something about diabetes - like a problem regulating insulin -- that contributes to Parkinson's. But that remains to be proven.

A few large studies have looked at the diabetes-Parkinson's link before, with conflicting results.

The current study, Chen said, included a larger number of people with Parkinson's. And unlike most past studies, it looked at the duration of people's diabetes.

In general, Chen's team found, the higher Parkinson's risk was largely seen among people who'd had diabetes for more than 10 years before the start of the study.

That, Chen said, supports the idea that diabetes came first, before Parkinson's, rather than the other way around.

But more studies, he said, are needed to understand why the connection exists, and what, if anything, can be done about it.

Source: http://bit.ly/hrUWrc

Diabetes Care, April 2011.

FDA examines link between food dyes, hyperactivity

By Mary Clare Jalonick

Associated Press

The Associated Press

Wednesday, March 30, 2011

WASHINGTON – Some evidence links dyes found in everyday foods to hyperactivity in certain children, scientists and academics told a Food and Drug Administration advisory committee Wednesday.

The panel is expected to weigh in Thursday on whether studies, some of which are decades old, definitively link the dyes and the disorder. The committee may recommend that the agency further regulate food coloring, do more studies or require better labeling of the additives. They also could also recommend that the FDA do nothing at all.

The FDA has so far said there is no proven relationship between food dyes and hyperactivity in most children. But the agency has agreed with many of the studies that say for "certain susceptible children," hyperactivity and other behavioral problems may be exacerbated by food dyes and other substances in food. Studies presented Wednesday backed that assertion.

The question for the agency is whether the potential effect on a possibly small percentage of children — it is unclear just how many — should lead to an outright ban of the additives or stricter warning labels on foods.

Public health advocates and academics studying the issue agree that dyes do not appear to be the underlying cause of hyperactivity, but they say that the effects of dyes on some children is cause enough to ban the additives.

The FDA is holding the meeting in response to a 2008 petition filed by the advocacy group Center for Science in the Public Interest to ban Yellow 5, Red 40 and six other dyes.

Michael Jacobson, the director of that group, said at the meeting Wednesday that the only reason that dyes exist in food is to trick consumers.

"Dyes are often used to make junk food more attractive to young children, or to simulate the presence of a healthful fruit or other natural ingredient," Jacobson said, adding that some manufacturers use less dyes in the same foods sold in Europe because of concerns there over hyperactivity. "Dyes would not be missed in the food supply except by the dye manufacturers."

Jacobson conceded that completely banning the dyes would be difficult and urged the FDA to at least put warnings on food package labels.

Scientists and public advocates have debated the issue for more than 30 years as the use of dyes in food has risen steadily — consumption of food coloring has doubled since 1990, according to some estimates. The advisory panel is sifting through a variety of studies over the two-day meeting, some showing more of a clear relationship between dyes and hyperactivity than others.

The food industry is warning consumers not to rush to judgment. David Schmidt, president and CEO of International Food Information Council Foundation, a food-industry funded group, said dyes help consumers enjoy their food by maintaining or improving appearance.

Suggesting a link between the color additives and attention deficit disorder in children "could have unintended consequences, including unnecessarily frightening consumers about safe ingredients that are consumed every day," he said.

Diet high in fish linked to stronger bones

By Kerry Grens

Reuters Health

Wednesday, March 30, 2011

NEW YORK (Reuters Health) – Older adults who eat greater amounts of fish end up preserving their bone density better than people who don't eat as much fish, a new study finds.

The study doesn't prove that such habits strengthen bones, but researchers believe that the combination of different oils in the fish protects bones from losing mass over time.

"We think omega 3 fatty acids from fish help to prevent" bone loss, said lead researcher Dr. Katherine Tucker, a professor at Northeastern University.

But her study finds that preventing bone loss is not as simple as upping the levels of omega 3 fats in people's diet.

Her group looked at surveys, collected in the 1980s and 90s, of the eating habits of more than 600 seniors who lived in Framingham, Massachusetts.

Measurements of the bone density in their hips were taken 4 years apart.

Women who ate three or more weekly servings of dark fish, such as salmon or mackerel, had smaller amounts of bone loss 4 years later, compared to women who ate less fish.

Men who ate dark fish or tuna at least three times per week also had less bone loss than other men.

The study was unable to show that fish was the cause of the differences in bone loss, but merely that the two are associated.

Fish are rich in the omega 3 fatty acids, EPA and DHA.

Looking further into what people ate, the researchers broke down how much of both omega 3 and omega 6 fatty acids people were getting in their diet.

They found that it's not just the omega 3s that are involved in bone density.

High levels of an omega 6 fatty acid, called arachidonic acid, was linked to less bone loss in women - but only when women also consumed higher levels of omega 3 fats.

"It looks like you need to have those in a good balance," Tucker told Reuters Health. "If you have very low levels of arachidonic acid, then you didn't see the benefits of the omega 3s."

"You can't just take a supplement of one and have a good effect," Tucker added.

Too much of one fat could actually be harmful.

In men, high arachidonic acid and low omega 3s was tied to greater loss of bone.

Tucker said there's no exact formula yet of omega 3 and omega 6 fats that would be good for bone health.

Fish appears to provide a good balance, Tucker said, because it has the omega 3 fats that tend to be lacking in Western diets. Omega 6 fatty acids are typically abundant in the food Americans eat.

The American Heart Association recommends that people eat two servings of fish each week.

Tucker's study, published in the American Journal of Clinical Nutrition, was funded by the National Institutes of Health.

Bone loss is a normal part of aging, and less dense bones are at a greater risk of breaking.

This study did not examine whether the differences in bone loss between frequent fish-eaters and others make any difference in the risk of breaking bones.

Source: http://bit.ly/hLozxB

American Journal of Clinical Nutrition, March 2, 2011.

Diet-Exercise Combo Seems to Work Best for Obese Seniors

By Randy Dotinga
HealthDay Reporter

HealthDay News

Wednesday, March 30, 2011

WEDNESDAY, March 30 (HealthDay News) -- A combination of diet and exercise can help obese seniors lose weight and stay fit much better than either diet or exercise alone, researchers reported Wednesday.

The finding may sound obvious, but the lead author of the new study said it had not been proven previously in people over 65.

In fact, some physicians worry about recommending dietary changes and exercise for older people for fear that weight loss may cause them to lose muscle and bone mass and increase their frailty, said geriatrics specialist Dr. Dennis T. Villareal, whose study is published in the March 31 issue of the New England Journal of Medicine.

But the findings suggest that older people, with approval from a physician, should combine diet and weight management "to improve their physical function and their quality of life and delay the need for institutionalization," Villareal said.

At least 20 percent of the elderly are obese -- a step above being simply overweight -- and that number will grow as more baby boomers age, Villareal added. He is currently chief of geriatrics at New Mexico VA Medical Center, but he started the research when he was at Washington University School of Medicine in St. Louis.

In a year-long trial, Villareal and his colleagues tracked the health of 93 obese people who were 65 or older. The participants were assigned to one of four groups: Some took part in a 90-minute exercise routine (including stretching, aerobic activity and training on weight machines) three times a week. Others reduced their diets by 500 to 700 calories a day, roughly equal to a couple of servings of low-sugar cereal with non-fat milk. A third group dieted and exercised, while a fourth group, acting as a control, did none of the programs.

Those who dieted and exercised did the best, losing 9 percent of their weight while retaining lean body mass, increasing oxygen consumption and improving their strength and balance. The diet-alone group lost 10 percent of their weight but did not achieve similar physical improvements.

And the exercise group, along with the control group, lost no weight.

It's not surprising that those who only exercised didn't shed pounds, Villareal said. "There's a myth that exercise is effective in inducing weight loss," he said, adding that exercise must be intense to cause people to shed pounds.

Overall, the researchers reported in their study, diet or exercise alone did improve physical function, by about 12 percent and 15 percent, respectively. But a combination of diet and exercise improved overall physical performance by 21 percent.

That's important because "obesity exacerbates the age-related decline in physical function, which causes frailty, impairs quality of life, and results in increases in nursing home admissions," they noted in the study.

The findings make sense, said Alice H. Lichtenstein, director of the Cardiovascular Nutrition Laboratory at Tuft University's Jean Mayer USDA Human Nutrition Research Center on Aging. "It's impressive that they were able to get the people to adhere to a diet and to engage in physical activity," she added.

More information

For more about obesity, try the U.S. National Library of Medicine.

Rates of diabetes-related amputation falling

By Genevra Pittman

Reuters Health

Wednesday, March 30, 2011

NEW YORK (Reuters Health) – Rates of foot and leg amputations in people with diabetes may have decreased in recent years, according to a new study of patients at Veterans Affairs (VA) clinics.

Total rates of amputation, taking into account the age and gender of patients, were about 7 for every 1,000 patients in 2000 and between 4 and 5 for every 1,000 in 2004.

The findings could mean "that we are getting better at screening patients ... and getting them the proper levels of care," Dr. James Wrobel, the head of the Center for Lower Extremity Ambulatory Research in North Chicago, Illinois, who was not involved in the study, told Reuters Health.

Close to 26 million Americans have diabetes, according to the American Diabetes Association. The National Institutes of Health reports that more than 65,000 people with diabetes had leg or foot amputations in 2006, the most recent year with available data.

Amputation is a risk with diabetes because nerve damage causes many patients to lose feeling in their feet, so they may not notice a cut or ulcer on their foot until it's infected. These cuts also take longer to heal because people with diabetes often have hardening of blood vessels, which causes less blood to flow to the feet and legs.

Previous studies have suggested that the rate of amputations in diabetics may be decreasing, but lead investigator Dr. Chin-Lin Tseng from New Jersey's Department of Veteran Affairs and colleagues were concerned that might be due to higher numbers of people being diagnosed with early diabetes who generally don't have serious leg problems.

While diabetes has been on the rise, the number of amputations wouldn't necessarily have increased yet. "Usually you don't see amputations in the first 10 years of somebody having diabetes," explained Wrobel.

In their analysis, published in Diabetes Care, the authors consulted records of all patients with diabetes that were seen at VA clinics and also tracked amputations in these patients paid for by Medicare. The study included between 400,000 and 800,000 patients with diabetes each year, most of whom were white and male.

When the researchers compared two similar populations and accounted for trends in earlier diabetes diagnoses, they calculated that amputation rates still decreased by about 20 percent during the study period.

Rates of minor and major amputations decreased at similar rates - in both 2000 and 2004, minor amputations were roughly twice as common as major amputations. However, the biggest decrease in amputation rates was in above-the-knee procedures - the most serious type of amputation the researchers examined.

Wrobel, who also works part-time at the VA, said it's hard to know if the findings are representative to the entire country, or if they are limited to VA clinics. He said that the VA has made improvements in screening patients with diabetes for foot problems and following their progress closely, and "the sum of all these things together could be explaining this," he said.

But some of those improvements in prevention and care are also probably happening in non-VA hospitals, Wrobel said.

When foot problems in patients with diabetes are caught early, treatments such as therapeutic shoes can cut down on their risk of later needing an amputation, Wrobel said.

"People with diabetes receive more aggressive treatment for their condition and its risk factors than previously, due to increased awareness of diabetes and targeted interventions," Dr. Eszter Vamos, who has studied amputation rates in diabetes patients at the Imperial College of London, told Reuters Health in an email.

Vamos, who was not involved in the current research, said that continued efforts are still needed to reduce the risk of amputation in patients with diabetes.

Source: http://bit.ly/i8tzDj

Diabetes Care, online March 16, 2011.

Most Americans Seem to Have Healthy Levels of Vitamin D

HealthDay News

Wednesday, March 30, 2011

WEDNESDAY, March 30 (HealthDay News) -- Nearly two-thirds of U.S. residents have sufficient levels of vitamin D levels, but about a fourth of the population is at risk for vitamin D inadequacy and 8 percent are at risk for vitamin D deficiency, a new federal government study indicates.

An additional 1 percent of Americans have vitamin D levels high enough that could be harmful, according to the report, released Wednesday by researchers at the U.S. National Center for Health Statistics, part of the U.S. Centers for Disease Control and Prevention.

The body needs vitamin D to help it absorb calcium, which is a requisite for healthy bones. Muscles and nerves need vitamin D to function properly, and it helps the immune system fight off disease. Too little can lead to thin, brittle bones; extremely high levels can be toxic.

Vitamin D can be absorbed naturally from sunlight or obtained through foods or dietary supplements.

The National Institute of Medicine defines sufficient vitamin D by the amount registered in the blood: as a serum 25-hydroxyvitamin D value of 50-125 nmol/L. A value of 30-49 nmol/L is defined as inadequacy and less than 30 nmol/L is considered a deficiency.

For their report, the researchers analyzed data from 2001 to 2006 from the National Health and Nutrition Examination Survey. It included people aged 1 and older.

The analysis showed that the risk for vitamin D deficiency differed by age, sex and race or ethnicity.

By age, the risk for deficiency ranged from 1 percent to 8 percent among males and from 1 percent to 12 percent among females. For both sexes, the risk was lowest among children aged 1 to 8 and increased significantly until age 30 in men and age 18 in women. After that, the risk changed little as people aged, the study found.

Whites were less likely to be at risk for vitamin D deficiency than blacks or Mexican-Americans.

Among women of childbearing age, those who were pregnant or lactating were less likely to be at risk for vitamin D deficiency than those who weren't pregnant or lactating.

Though vitamin D deficiency became more common in the United States between 1988-1994 and 2001-2002, the study found, risk for the deficiency did not change between 2001-02 and 2005-06.

About 4 percent of males 12 years and older had vitamin D levels that put them at risk for deficiency in 1988-1994, and 17 percent were at risk for inadequacy. Those numbers had risen to 7 percent and 22 percent, respectively, by 2001-2002, according to the study.

Among females 12 and older, vitamin D deficiency rose from 7 percent in 1988-1994 to 11 percent in 2001-2002. However, the proportion of females with inadequate levels of vitamin D dropped from 30 percent to 25 percent in that time.

More information

The Office of Dietary Supplements at the U.S. National Institutes of Health has more about vitamin D.

Tuesday, March 29, 2011 

MRSA Infections May Vary by Season

ScienceDaily

Tuesday, March 29, 2011

TUESDAY, March 29 (HealthDay News) -- Dangerous methicillin-resistant staphylococcus aureus, or MRSA, infections occur more often in the summer and fall, and this seasonal increase is more common in children than adults, a new study reports.

The findings came from an analysis of MRSA cases that occurred at Rhode Island Hospital, in Providence, over 10 years.

The researchers found that children's infections were higher in the third and fourth quarters of the year than in the first two quarters. In the later months, children had 1.85 times more MRSA infections that had been contracted outside of a health-care setting, called community-associated MRSA infections, and 2.94 times more hospital-associated infections.

By contrast, adults had 1.14 times more community-associated MRSA infections in the last two quarters of the year than in the first two quarters, and there was no seasonal variation in hospital-associated infections, according to the study, published online March 23 in PLoS One.

The researchers also reviewed published articles from the past 70 years, finding an increase in MRSA infections during summer and autumn in many temperate regions of the world and during the warmest months of the year in tropical regions.

Skin moisture plays an important role in the growth of microbes, and the presence of both heat and humidity may offer ideal conditions for the proliferation of S. aureus, the researchers said.

"It is hoped that this study will promote further investigation into the seasonality of S. aureus infections to better understand the biologic basis for this observation," lead author Leonard Mermel, medical director of the department of epidemiology and infection control at Rhode Island Hospital, said in a hospital news release.

More information

The U.S. Centers for Disease Control and Prevention has more about MRSA infections.

Evidence ties smoking to throat, stomach cancer

By Amy Norton

Reuters Health

Tuesday, March 29, 2011

NEW YORK (Reuters Health) – Smokers face an increased risk of certain types of throat and stomach cancers, even years after they quit, a new study finds.

Combining the results of 33 past studies, Italian researchers found that current smokers were more than twice as likely as nonsmokers to develop cancer, either in their esophagus or in a part of the stomach called the gastric cardia.

In some of the studies, the risk of esophagus cancer remained high even when people had quit smoking three decades earlier.

The two cancers, both known as adenocarcinomas, are relatively uncommon in Western countries. Rates elsewhere are much higher, especially in less developed countries. But in recent decades, rates of the cancers have been rising in the U.S. and Europe -- possibly related to growing rates of obesity.

Smoking has long been considered a risk factor for the two cancers.

But these latest findings offer a "better quantification" of the risks, said senior researcher Dr. Eva Negri, of the "Mario Negri" Institute of Pharmacological Research in Milan.

What's more, they suggest that the risks remain higher than average for some time after smokers quit.

"Stopping smoking is highly beneficial at any age, but it appears that for these cancers the risk decreases only slowly," Negri told Reuters Health in an email.

For their study, published in the journal Epidemiology, Negri and her colleagues pooled the results of 33 previous studies. In most of them, researchers had compared a relatively small group of patients with either esophagus or gastric cardia tumors against a cancer-free group. In three studies, researchers had followed large groups of adults over time, charting any new cases of esophageal or gastric cardia cancers.

Overall, Negri's team found, current smokers had more than double the odds of developing either of the cancers, compared to people who had never smoked.

And while that risk declined after people stopped smoking, it was still 62 percent higher in former smokers than in lifelong non-smokers. In some studies, the extra risk of esophagus cancer persisted up to 30 years after people had quit.

Since both esophageal and gastric cardia adenocarcinomas are fairly uncommon in the West, the absolute risks to any one smoker may be low.

According to the American Cancer Society, the average American has a one in 200 chance of developing any type of esophageal cancer over a lifetime, and a one in 114 risk of developing some form of stomach cancer.

By comparison, the odds of developing lung cancer are about one in 13 for men, and one in 16 for women -- counting both smokers and non-smokers. Smokers would be at much greater risk than lifelong non-smokers.

Lung cancer, heart disease and other ills are "numerically more important" than esophageal and gastric cardia cancers when it comes to the health consequences of smoking, Negri noted.

The types of studies that were available for her team to analyze can't prove that smoking causes adenocarcinoma of the esophagus or gastric cardia. To do that, researchers would have to purposely expose some people to years of tobacco smoke and see what happens to them over time - and ethical reasons make a study like that impossible.

Still, Negri and her colleagues say, the risks seen in the current study offer smokers one more reason to quit -- and non-smokers one more reason to never start.

Source: http://bit.ly/hQnt5V

 

Epidemiology, online February 16, 2011.

Marijuana Use May Hurt Intellectual Skills in Multiple Sclerosis Patients

ScienceDaily

Tuesday, March 29, 2011

ScienceDaily (Mar. 29, 2011) — Any possible pain relief that marijuana has for people with multiple sclerosis (MS) may be outweighed by the drug's apparent negative effect on thinking skills, according to research published in the March 29, 2011, print issue of Neurologyฎ, the medical journal of the American Academy of Neurology.

Some clinical trials have reported a mild benefit of marijuana on pain, bladder dysfunction and spasticity in MS, an auto-immune disease that affects the brain and spinal cord.

The researchers studied two groups of 25 people each between the ages of 18 and 65 with MS. One group used marijuana and the other reported no marijuana use for many years. Urine tests were used to confirm use or non-use of the drug. The groups were matched so there would not be significant differences due to age, gender, level of education, IQ before diagnosis, level of disability and duration of time with MS.

On average, the duration of marijuana use was 26 years. A total of 72 percent of users reported smoking marijuana on a daily basis while 24 percent reported weekly use and one person reported bi-weekly use.

Participants' cognitive skills were tested. The research found that people who used marijuana performed significantly worse with respect to attention, speed of thinking, executive function and visual perception of spatial relationships between objects. For example, on a sensitive test of information processing speed, those using marijuana scored approximately one third lower than non-users. Those who used marijuana were also twice as likely as non-users to be classified as globally cognitively impaired, defined as impairment on two or more aspects of intellectual functioning.

"Given that about 40 to 60 percent of MS patients have problems with cognitive function to begin with, any drug that may add to this burden is cause for concern," said study author Anthony Feinstein, MPhil, MD, PhD, with Sunnybrook Health Services Center and the University of Toronto in Ontario, Canada. "This study provides empirical evidence that prolonged use of inhaled or ingested marijuana in MS patients is associated with poorer cognitive performance, and these effects have to be weighed against any possible benefit of using marijuana for medicinal purposes."

The study was supported by the Multiple Sclerosis Society of Canada.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

K. Honarmand, M. C. Tierney, P. O'Connor, A. Feinstein. Effects of cannabis on cognitive function in patients with multiple sclerosis. Neurology, 2011; 76 (13): 1153 DOI: 10.1212/WNL.0b013e318212ab0c

Less Stress, Better Sleep May Help You Lose Weight

By Steven Reinberg
HealthDay Reporter

HealthDay News

Tuesday, March 29, 2011

TUESDAY, March 29 (HealthDay News) -- If you're looking to lose those extra pounds, you should probably add reducing stress and getting the right amount of sleep to the list, say researchers from Kaiser Permanente's Center for Health Research in Portland.

In fact, although diet and exercise are the usual prescription for dropping pounds, high stress and too little sleep (or too much of it) can hinder weight loss even when people are on a diet, the researchers report.

"We found that people who got more than six but less than eight hours of sleep, and who reported the lowest levels of stress, had the most success in a weight-loss program," said study author Dr. Charles Elder.

Elder speculates if you are sleeping less or more than recommended and if your stress levels are high, you will not be able to focus on making behavioral changes.

These factors may also have a biological impact, he added.

"If you want to lose weight, things that will help you include reducing stress and getting the right amount of sleep," Elder said.

The report, funded by the U.S. National Institutes of Health, is published in the March 29 online edition of the International Journal of Obesity.

In this two-step trial, 472 obese adults were first counseled about lifestyle changes over a 26-week period. Recommendations included cutting 500 calories a day, eating a diet rich in fruits, vegetables and whole grains by following the Dietary Approaches to Stop Hypertension (DASH) diet approach, and exercising at least three hours a week.

In addition, the researchers asked the participants questions about sleep time, depression, insomnia, screen time and stress.

During this part of the trial, the participants lost an average of almost 14 pounds. The 60 percent of the participants who lost at least 10 pounds went on to take part in the next phase of the trial. Those in the second phase of the trial continued their diet and exercise program.

Elder's team found the right amount of sleep and stress reduction at the start of the trial predicted successful weight loss. Lower stress by itself predicted more weight loss during the first phase of the trial, they added.

Declines in stress and depression were also important in continuing to lose weight during both phases of the trial, as were exercise minutes and keeping food diaries, Elder's group found.

Dr. David L. Katz, director of the Prevention Research Center at Yale University School of Medicine, said that "while we often tend to look at health one condition at a time, the reality is that health is best viewed holistically."

"People who are healthy and vital tend to be healthy and vital not because of any one factor, but because of many. And the factors that promote health -- eating well, being active, not smoking, sleeping enough, controlling stress, to name a few --promote all aspects of health," he added.

This study shows that people are more likely to lose weight when not impeded by sleep deprivation, stress or depression, he said.

"Anyone who has ever tried to lose weight probably could have said much the same from personal experience. Similarly, weight loss reduced stress and depression. This, too, is suggested by sense and common experience, as it is affirmed by the science reported here," Katz said.

The important message is that weight loss should not be looked at with tunnel vision, Katz said.

"Improving sleep may be as important to lasting weight control efforts as modifying diet or exercise. Managing stress is about physical health, as well as mental health. This study encourages weight loss in a more holistic context," he said.

Another study presented earlier this month at the American Heart Association scientific sessions held in Atlanta found that people of normal weight eat more when they sleep less.

Columbia University researchers discovered that sleep-deprived adults ate almost 300 calories more a day on average than those who got enough sleep. And the extra calories mostly came from saturated fat, which can spell trouble for waistlines.

The researchers came to their conclusions -- which should be considered preliminary until published in a peer-reviewed journal -- after following 13 men and 13 women of normal weight. They monitored the eating habits of the participants as they spent six days sleeping four hours a night and then six days sleeping nine hours a night (or the reverse).

"If sustained, the dietary choices made by people undergoing short sleep could predispose them to obesity and increased risk of cardiovascular disease," the researchers wrote in an American Heart Association news release.

More information

For more information on obesity, visit the U.S. National Library of Medicine.

Antioxidant Formula Prior to Radiation Exposure May Prevent DNA Injury, Trial Suggests

ScienceDaily

Tuesday, March 29, 2011

ScienceDaily (Mar. 29, 2011) — A unique formulation of antioxidants taken orally before imaging with ionizing radiation minimizes cell damage, noted researchers at the Society of Interventional Radiology's 36th Annual Scientific Meeting in Chicago, Ill. In what the researchers say is the first clinical trial of its kind, as much as a 50 percent reduction in DNA injury was observed after administering the formula prior to CT scans.

"In our initial small study, we found that pre-administering to patients a proprietary antioxidant formulation resulted in a notable dose-dependent reduction in DNA injury," said Kieran J. Murphy, M.D., FSIR, professor and vice chair, director of research and deputy chief of radiology at the University of Toronto and University Health Network, Toronto, Ontario, Canada. "This could play an important role in protecting adults and children who require imaging or a screening study," he added.

"Pre-administering this formula before a medical imaging exam may be one of the most important tools to provide radioprotection and especially important for patients in the getting CT scans," said Murphy. The study's data support the theory about a protective effect during these kinds of exposure, he explained.

"There is currently a great deal of controversy in determining the cancer risks associated with medical imaging exams. Although imaging techniques, such as CT scans and mammograms, provide crucial and often life-saving information to doctors and patients, they work by irradiating people with X-rays, and there is some evidence that these can, in the long run, cause cancer," explained Murphy. The interventional radiologist researchers responded to this patient need by exploring a way to protect individuals from these potentially harmful effects. This may be of importance to interventional and diagnostic radiologists and X-ray technologists who have occupational exposure also.

The small study showed that even though many antioxidants are poorly absorbed by the body, one particular mixture was effective in protecting against the specific type of injury caused by medical imaging exams. People are 70 percent water, and X-rays collide with water molecules to produce free radicals (groups of atoms with an unpaired number of electrons that are dangerous when they react with cellular components, causing damage and even cell death) that can go on to do damage by direct ionization of DNA and other cellular targets, noted Murphy. The research team evaluated whether a special combination of antioxidants have an ability to neutralize these free radicals before they can do damage.

"Our intent was to develop an effective proprietary formula of antioxidants to be taken orally prior to exposure that can protect a patient's DNA against free radical mediated radiation injury, and we have applied to patent this formulation and a specific dose strategy," said Murphy.

The experiments measured DNA damage as a surrogate marker for DNA injury. Blood was drawn from two study volunteers in duplicate, creating four individual tests per data point. DNA strand breaks are repaired by a big protein complex that binds to the site of the damage. The researchers labeled one of the proteins with a fluorescent tag. Then, under a powerful 3-D microscope, the DNA is examined for signs of repair. The more repair that is seen, the more DNA damage must have been done by the CT scan to initiate that repair. The experiments clearly showed a reduction of DNA repair in the treatment group, which means that there was less DNA injury as a result of pre-administering the antioxidant mixture, said Murphy.

The researchers concede that this is a small study and that a lot more research needs to be done; however, these initial results point toward a positive future for this kind of treatment. The group says the next step is a clinical trial in Toronto.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Too many old men get prostate cancer tests: study

By Genevra Pittman

Reuters Health

Tuesday, March 29, 2011

NEW YORK (Reuters Health) – Many men in their 80s get regular blood tests for prostate cancer even though there's no evidence the tests will benefit them, according to a new study.

In older men, finding hidden prostate cancer might not be helpful, because the cancer might not shorten their lifespan. But once it's discovered, a very early-stage cancer usually leads to painful and expensive medical encounters.

So with elderly men, screening "makes no sense," Dr. Peter Albertsen, a prostate cancer researcher at University of Connecticut Health Center in Farmington who was not involved with the current study, told Reuters Health.

The researchers also found that men in their 70s were almost twice as likely as men in their 50s to have a blood test that looks for signs of prostate cancer - even though younger men have the best chance to benefit from screening.

"Those younger men are the ones the test was designed for," Dr. Scott Eggener, one of the study's authors from the University of Chicago Medical Center, told Reuters Health. But older men "are far more likely to see their doctor regularly," and doctors may be used to ordering the prostate cancer blood tests in these men without really thinking about it, he said.

The findings, published in the Journal of Clinical Oncology, come amid a debate in the medical community on whether routine cancer screening can extend lives.

The blood test in question looks for a protein produced by the prostate called prostate-specific antigen, or PSA. As the National Institutes of Health explains on its web site, the higher a man's PSA level, the more likely it is that he has prostate cancer. A man can have an elevated PSA level without having cancer, though.

To estimate national rates of PSA screening, Eggener and his colleagues consulted data from two country-wide health surveys that had been conducted in 2000 and 2005. The surveys asked almost 15,000 men whether they had been screened for prostate cancer in the past year.

Twenty-four percent of men in their early 50s said they had been screened. More men reported recent screening as age increased, with about 46 percent of men in their early 70s having been screened. Rates declined again once men passed the age of 74, but about 25 percent of men age 85 and older still said they had been screened in the past year.

Scaling those numbers up to reflect the entire U.S. population, the authors calculated that about 1.5 million men in their 80s and older had a PSA screening test recently.

While catching prostate cancer early can prevent the disease from progressing, men with a positive reading are subjected to biopsies and sometimes treatment, involving uncomfortable procedures that carry risks of complications and side effects.

Especially with older men or those with other chronic diseases, it's possible that the risk is for nothing, and that having undetected cancer wouldn't have cut any time from their lives.

Screening patients who won't really benefit also adds unnecessary costs to the health system. The average cost of a PSA test is estimated to range from $70 to $400 dollars. Medicare will pay for 80 percent of the cost, but some private insurance companies won't cover PSA screening at all.

Dr. Steven Woloshin, who studies the risks and benefits of cancer screening at Dartmouth Medical School in Hanover, New Hampshire, said that even in younger men, there is not much evidence that prostate screening can prevent deaths.

"There's a small chance or maybe no chance of benefit," Woloshin, who also did not participate in the new study, told Reuters Health, "but there's certainly a possibility of harm" in the form of unnecessary tests and treatment.

The U.S. Preventive Services Task Force, a federal expert panel, reported in 2008 that the benefits of screening for prostate cancer in men younger than 75 are "uncertain," and that the harms probably outweigh any benefits for men 75 and older.

It's hard to know if that message is being communicated to men who are considering screening, Woloshin said.

Eggener said that men should be aware of the benefits and risks of PSA screening, and that neither patients nor doctors should assume that getting screened is always the right way to go.

"The optimal way of doing it is for both patients and physicians to have a meaningful conversation about, 'should I get this test or should I not?'" Eggener said.

Source: http://bit.ly/efOaBn

 

Journal of Clinical Oncology, online March 29, 2011.

 

Monday, March 28, 2011 

Teens Who Smoke Early Often Try Pot Later, Study Finds

HealthDay News

Monday, March 28, 2011

MONDAY, March 28 (HealthDay News) -- Teenagers who begin smoking at an early age are much more likely to start using marijuana by the time they're 17, researchers report.

Their analysis of data from a Finnish-American birth cohort study that began in 1994 found that by the time they were 17, about 15 percent of girls and 12 percent of boys had used marijuana or other illicit substances at least once.

Predictors of drug use included being female, binge drinking, father's binge drinking, peers who smoked, acquaintances with drug experience, and aggressive behavior among boys.

The researchers also found that starting smoking at an early age was an especially strong predictor of drug use. Participants who started smoking by age 12 or earlier were 26 times more likely to start using drugs by age 17 than those who never smoked.

"The findings support the gateway hypothesis, which asserts that illicit substances such as tobacco and alcohol are a stepping stone to harder, illicit drugs," project team member Tellervo Korhonen, of the University of Helsinki, said in an Academy of Finland news release. The academy funded the project.

"The theory has come under much criticism in recent years. Many have argued that certain common factors may explain both smoking and drug use, factors such as problem behavior and genetic influences. That's why we wanted to look into these issues more deeply in our studies," Korhonen added.

The findings appeared recently in the Journal of the American Academy of Child and Adolescent Psychiatry.

More information

The U.S. Centers for Disease Control and Prevention has more about youth and tobacco.

Avoiding Health Risks Could Prevent More Than Half of All Cases of Atrial Fibrillation

ScienceDaily

Monday, March 28, 2011

ScienceDaily (Mar. 28, 2011) — Reducing cardiovascular risk factors like high blood pressure, smoking, diabetes and being overweight could potentially reduce more than half of all cases of atrial fibrillation, according to research reported in Circulation: Journal of the American Heart Association.

More than 2 million Americans live with atrial fibrillation (AF), an irregular heart rhythm that occurs when the heart's two upper chambers beat erratically, causing the chambers to pump blood rapidly, unevenly and inefficiently. Blood can pool and clot in the chambers, increasing the risk of stroke or heart attack. AF affects about 3 percent to 5 percent of people over age 65 and is related to about 15 percent of all strokes.

"We now know that a significant proportion of all cases of atrial fibrillation can be avoided," said Alvaro Alonso, M.D., M.P.H., Ph.D., co-author of the study and assistant professor of epidemiology and community health at the University of Minnesota School of Public Health in Minneapolis. "Ideally, if individuals were able to maintain a normal blood pressure and healthy body weight and didn't smoke, not only would it reduce their risks for other forms of cardiovascular disease, such as heart disease and stroke, but it also would significantly impact the risk of developing atrial fibrillation in later life."

In the study, 57 percent of the AF episodes were linked to specific risk factors, including high blood pressure, smoking, diabetes, overweight and other heart diseases. Of these risks, high blood pressure was the strongest predictor, accounting for more than one-fifth of all cases.

The researchers also identified gender and racial differences in risk factor prevalence, with more than 80 percent of African Americans having one or more risk factors compared to 60 percent of whites. Only about 2 percent of African-American men and African-American women had optimal risk factors versus 3 percent white men and 10 percent of white women with optimal risk.

"A lot of work needs to be done to try to ensure that African-Americans in particular achieve optimal levels of blood pressure and diabetes control," said Rachel R. Huxley, D.Phil., lead author and associate professor of epidemiology and community health at the University of Minnesota School of Public Health.

Only 5 percent of participants overall had optimal levels of risk factors for preventing AF. Slightly more than one-fourth were classified as having a borderline risk factor profile and two-thirds of study participants had elevated risk factor levels. Patients with optimal levels of risk factors had one-third of the risk of developing AF compared with those with an elevated risk factor profile.

During the study, 1,520 episodes of AF occurred.

Population risk estimates showed that having one or more elevated risk factor level could explain 50 percent of AF events. In whites, the risk was 50 percent in women and 38.2 percent in men. In African Americans, the risk of AF associated with having one or more elevated risk factors was 94 percent in women and 91 percent in men.

The study comprised 14,598 participants in the Atherosclerosis Risk in Communities Study (ARIC), a prospective study of heart disease among residents of four communities in North Carolina, Mississippi, Maryland and Minnesota. Their average age was 54 years old, 55 percent were women, 75 percent were white and 25 percent were African-American. The study started in 1987, and follow-up averaged 17 years.

After an initial interview and medical exam, investigators divided participants into one of three groups based on their risk factors for AF: optimal, borderline and elevated. Patients in the optimal-risk group had normal blood pressure and weight, no heart disease or diabetes, and no smoking history.

Patients in the other two groups had increased risks in these categories.

Other co-authors are: Faye L. Lopez, M.P.H.; Aaron R. Folsom, M.D., M.P.H.; Sunil K. Agarwal, M.D., M.P.H., Ph.D.; Laura R. Loehr, M.D., M.S., Ph.D.; Elsayed Z. Soliman, M.D., M.Sc., M.S.; Rich Maclehose, Ph.D.; and Suma Konety, M.D., M.S.

The National Heart, Lung, and Blood Institute and the American Heart Association funded the study.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

Rachel R. Huxley, Faye L. Lopez, Aaron R. Folsom, Sunil K. Agarwal, Laura R. Loehr, Elsayed Z. Soliman, Rich Maclehose, Suma Konety, and Alvaro Alonso. Absolute and Attributable Risks of Atrial Fibrillation in Relation to Optimal and Borderline Risk Factors: The Atherosclerosis Risk in Communities (ARIC) Study. Circulation, 2011; DOI: 10.1161/CIRCULATIONAHA.110.009035

High Blood Pressure in Doc's Office Not Always Hypertension

HealthDay News

Monday, March 28, 2011

MONDAY, March 28 (HealthDay News) -- One-third of patients with resistant high blood pressure have so-called "white coat hypertension," a new study suggests.

White coat hypertension is when a patient's blood pressure is high at the doctor's office but in the normal range in everyday life. Resistant hypertension refers to blood pressure that remains above treatment goals despite taking three different types of drugs at the same time.

In this study, Spanish researchers used 24-hour ambulatory monitoring to check the blood pressure of 69,045 patients, average age 64, diagnosed with hypertension. The ambulatory monitoring involved regular blood pressure checks every 20 minutes under normal living and working conditions.

The researchers found that 37 percent of the 8,295 patients diagnosed with resistant hypertension actually had white coat hypertension, and that more women than men had white coat hypertension -- 42 percent versus 34 percent.

Patients with true resistant hypertension were slightly younger, more often male, had high blood pressure for a longer period of time and had a worse cardiovascular risk profile. This group included a larger number of smokers, diabetics and patients with ventricular hypertrophy and previous cardiovascular disease.

The study is published in the current issue of the journal Hypertension.

"Ambulatory blood pressure monitoring should be mandatory in resistant hypertension patients to define true and 'white coat' hypertension," lead author Dr. Alejandro de la Sierra, director of internal medicine at Hospital Mutua Terrassa, University of Barcelona, said in an American Heart Association news release.

"Patients benefit by knowing whether their blood pressure is normal during daily activities or still needs the reinforcement of dietary and drug measures to achieve the goal," according to de la Sierra.

More information

The U.S. National Heart, Lung, and Blood Institute has more about high blood pressure.

Sunday, March 27, 2011 

Walnuts Are Top Nut for Heart-Healthy Antioxidants

ScienceDaily

Sunday, March 27, 2011

ScienceDaily (Mar. 27, 2011) — A new scientific study positions walnuts in the number one slot among a family of foods that lay claim to being among Mother Nature's most nearly perfect packaged foods: Tree and ground nuts. In a report given in Anaheim, California at the 241st National Meeting & Exposition of the American Chemical Society on March 27, scientists presented an analysis showing that walnuts have a combination of more healthful antioxidants and higher quality antioxidants than any other nut.

"Walnuts rank above peanuts, almonds, pecans, pistachios and other nuts," said Joe Vinson, Ph.D., who did the analysis. "A handful of walnuts contains almost twice as much antioxidants as an equivalent amount of any other commonly consumed nut. But unfortunately, people don't eat a lot of them. This study suggests that consumers should eat more walnuts as part of a healthy diet."

Vinson noted that nuts in general have an unusual combination of nutritional benefits -- in addition those antioxidants -- wrapped into a convenient and inexpensive package. Nuts, for instance, contain plenty of high-quality protein that can substitute for meat; vitamins and minerals; dietary fiber; and are dairy- and gluten-free. Years of research by scientists around the world link regular consumption of small amounts of nuts or peanut butter with decreased risk of heart disease, certain kinds of cancer, gallstones, Type 2 diabetes, and other health problems.

Despite all the previous research, scientists until now had not compared both the amount and quality of antioxidants found in different nuts, Vinson said. He filled that knowledge gap by analyzing antioxidants in nine different types of nuts: walnuts, almonds, peanuts, pistachios, hazelnuts, Brazil nuts, cashews, macadamias, and pecans. Walnuts had the highest levels of antioxidants.

Vinson also found that the quality, or potency, of antioxidants present in walnuts was highest among the nuts. Antioxidants in walnuts were 2-15 times as potent as vitamin E, renowned for its powerful antioxidant effects that protect the body against damaging natural chemicals involved in causing disease.

"There's another advantage in choosing walnuts as a source of antioxidants," said Vinson, who is with the University of Scranton in Pennsylvania. "The heat from roasting nuts generally reduces the quality of the antioxidants. People usually eat walnuts raw or unroasted, and get the full effectiveness of those antioxidants."

If nuts are so healthful and nutritious, why don't people eat more? Vinson's research shows, for instance, that nuts account for barely 8 percent of the daily antioxidants in the average person's diet. Many people, he said, may not be aware that nuts are such a healthful food. Others may be concerned about gaining weight from a food so high in fat and calories. But he points out that nuts contain healthful polyunsaturated and monosaturated fats rather than artery-clogging saturated fat. As for the calories, eating nuts does not appear to cause weight gain and even makes people feel full and less likely to overeat. In a 2009 U. S. study, nut consumption was associated with a significantly lower risk of weight gain and obesity. Still, consumers should keep the portion size small. Vinson said it takes only about 7 walnuts a day, for instance, to get the potential health benefits uncovered in previous studies.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.